Catalytic Decoupling of Quantum Information

Understand

The decoupling technique is a fundamental tool in quantum information theory with applications ranging from quantum thermodynamics to quantum many body physics to the study of black hole radiation.

• In this work we introduce the notion of catalytic decoupling, that is, decoupling in the presence of an uncorrelated ancilla system.
• This removes a restriction on the standard notion of decoupling, which becomes important for structureless resources, and yields a tight characterization in terms of the max-mutual information.
• Catalytic decoupling naturally unifies various tasks like the erasure of correlations and quantum state merging, and leads to a resource theory of decoupling.